U.S. probes potential risks of cancer, flu, MS drugs

WASHINGTON (Reuters) - U.S. health regulators are reviewing potential risks of several widely used medicines.

The Food and Drug Administration said on Wednesday it was probing reports of hearing loss with Novartis cancer drug Gleevec, hypothermia with Roche's flu drug Tamiflu and pericarditis with Biogen Idec and Elan Corp's multiple sclerosis drug Tysabri.

The FDA releases a quarterly list of safety probes to inform the public about early investigations of potential side effects that have been reported. The lists released on Wednesday covered issues identified between April 2009 and September 2009. More than two dozen drugs were listed.

Others included rheumatoid arthritis drugs known as tumor necrosis factor (TNF blockers) for reports of demyelinating neuropathy, a neurological disorder. The FDA did not name specific TNF blockers, but the drug include Amgen and Pfizer's Enbrel, and Abbott Laboratories Inc's Humira.

Being on the list "does not mean that FDA has identified a causal relationship between the drug and the listed risk," the FDA said.

Roche spokeswoman Tara Cooper said the company "will work with the FDA to better understand the reports of hypothermia" listed for Tamiflu.

"As noted by the FDA, this is early information and inclusion on this list does not constitute a potential safety signal or causal relationship," she said.

Officials at other drugmakers had no immediate comment or could not immediately be reached.